A structure that carries a highway over an obstruction.

• A. Through Bridge
• B. Highway Bridge
• C. Deck Bridges
• D. Cantilever Bridges

Answer: (B)

A highway bridge is the structure that carries a highway over an obstruction. Its main purpose is to span the obstacle—such as a river, valley, or other barrier—and transfer the loads from the highway deck to the supports beneath. The terms through, deck, and cantilever describe how the bridge is built or the arrangement of its members, not the basic function of carrying a highway over an obstacle. A through bridge carries traffic through the structure’s framework, a deck bridge places the deck on top with supporting elements below, and a cantilever bridge uses projecting arms that balance and meet to form the span. The essential idea is that the structure’s role is to carry a highway across an obstruction, which is exactly what a highway bridge does.